Combine PDFs and print four pages per sheet

Combine several PDF files and print them four per page when a packet should read as one ordered document. PdfNUp joins the supplied files in their upload order, then places each group of four source pages into a 2 by 2 grid on an A4 sheet.

Prepare the source files in reading order

First, decide which file should come first and place the PDFs in that sequence before uploading. The service concatenates pages in file order and within each PDF's own page order; it does not sort filenames or infer that an invoice should follow a delivery note. If a cover page, appendix, or instruction page belongs at the front, include it in the right position. Keep the original files nearby so you can compare page numbers and confirm the order after processing.

Check that each input is a PDF and that the combined source set fits the limits: up to 20 files, 50 MiB per file, and 500 pages in total. Damaged, unsupported, or encrypted files that require an opening password are not usable. A PDF that restricts printing is also refused, while an owner-restricted PDF that still permits printing can be accepted. Remove any file that is not part of the intended packet rather than expecting the service to recognize its purpose.

Before upload, inspect the first and last page of every file and note any pages that should not appear in the printed packet. Four-up includes source pages in sequence; it does not select only pages with text or remove blank pages. If a source has a blank reverse or an internal separator, that page occupies one of the four cells like any other page. For a sensitive document, use a copy prepared under your organization's retention and access rules.

Run the four-up workflow

1. Open the PdfNUp service page and choose the PDFs in the exact order you want them read.
2. Set pages per sheet to 4. The supported setting is an integer from 1 to 64; four produces the familiar two-column, two-row arrangement.
3. Start processing and wait for the asynchronous action to finish.
4. Download the resulting PDF from the action results and open it in a standard PDF reader.

The service costs 10 tokens per successful run. It performs the layout locally within MXPROCESS and does not send the document to an external AI provider. The returned file is one A4 PDF. Each source page is reduced proportionally and centered in its cell; it is not stretched to match the cell's shape. This is especially useful when a packet contains a mixture of page sizes or portrait and landscape pages.

The grid is calculated for the number of pages requested: four is 2 by 2, nine is 3 by 3, and six is 3 by 2. The last output sheet may have empty cells if the total is not divisible by four. Sheet cells keep the same dimensions throughout the document, including that final sheet, so its occupied pages do not expand to fill the spare spaces. That makes page scale predictable from one sheet to the next.

Check the output before sending it to a printer

Open the downloaded file and review its page count. For four-up, divide the source total by four and round up; a 23-page set should produce six output sheets. Compare the opening pages with the source sequence, then check a page near every file boundary. This catches a wrong upload order or a missing source before paper is used. Inspect the final output page as well, since a partial grid is expected when there is a remainder.

Use the PDF reader's zoom to inspect small labels, then check the print preview at the intended paper size. A vector-preserving output is not a screenshot: text can remain selectable, and fine line work is not rasterized into a single image by this action. Selection alone does not guarantee that every font or symbol is legible at four-up scale. If a page includes tiny footnotes or a dense table, print fewer pages per sheet or keep that page at full size in a separate copy.

Mixed orientations are handled inside the grid, but a page that is landscape in the source remains a landscape page that has been proportionally fitted into its cell. It is not rotated or cropped just to occupy the available rectangle. A sample print can show whether the resulting orientation is comfortable to read. Disable extra scaling in the printer dialog if it would change the layout, and verify duplex settings separately if using both sides of the paper.

Keep a repeatable packet process

For a recurring packet, use a short checklist: source names, intended sequence, expected source count, chosen density, and output page count. Save the original inputs in the appropriate controlled location and label the output so that readers can distinguish it from the source PDFs. If a later revision arrives, rebuild from the revised sources rather than editing a flattened print preview. That reduces the risk that a stale page survives in a packet.

When someone else will print the file, tell them that each output page contains four source pages and that the document is meant to be printed at its A4 page size. Ask them not to apply another N-up setting in the printer driver. A second four-per-sheet operation can shrink the already compact grid again. If the printer previews a result that differs from the PDF reader, resolve that setting before releasing the job.

If conserving paper is the main goal, the guide to choosing a readable paper-saving density explains how to compare sheet counts with audience needs. To prepare the file now, combine your PDFs into a four-up A4 document and inspect the result before printing.

Four-up workflow questions

Can the final sheet contain fewer than four pages?

Yes. The output retains the same cell size on every sheet, and unused cells remain empty on a partial final page. Pages are not stretched to fill those cells.

Will it rotate a portrait page to fill a landscape cell?

No. Each page is scaled proportionally and centered, preserving its proportions. Mixed page sizes and orientations can share a document without being distorted.

Can I send the request through the API?

Yes. The authenticated multipart endpoint accepts files as file0 through file19 and a parameters value such as {"pagesPerSheet":4}; it returns the normal asynchronous action response with a tracking URL.